Alcohol reformate is superior to the parent alcohol as a fuel for internal combustion engines. The superiority of alcohol reformate, particularly those formed from methanol and ethanol, is primarily due to the presence of hydrogen. Reformate burns faster than the starting alcohol and is more tolerant of dilution with air or exhaust. At part load, dilution benefits efficiency by reducing throttling losses and loss of heat of combustion to the coolant. In addition, the heat of combustion of reformate is greater than that of the starting alcohol. Both alcohols and reformate are high octane fuels which can tolerate high compression ratios.